The present invention relates generally to containers and, in particular, to containers containing unmixed two-part liquid compounds. The invention includes a method and kit for packaging such compounds.
A variety of chemical compounds, such as two component epoxy coatings, urethane paints, polymeric coatings, multi-part resinous materials, e.g., coatings and adhesives, and the like, include two parts, which comprise a base material, such as a polymer or monomer resin, to which an accelerator or catalyst is added just prior to use. The two components must be stored separately and mixed together shortly before use. Some of these compounds require the admixture of multiple components just prior to use. These compounds may comprise an epoxy or urethane base to which a curing agent, catalyst, accelerator or hardener is added in a predetermined proportion just prior to use of the material. Additional components may include colorants, texturizers, fillers and so on. After mixing, the composition can then be used for its intended purpose.
A variety of containers for holding multiple components separate from one another have been suggested. One example (U.S. Pat. No. 5,083,674) includes a two-compartment container for epoxy adhesives including an upper and lower pail shaped container, each including a removable cover. The lower end of the upper container is bonded to the cover of the lower container so that both containers form a unitary structure when the cover is in place on the lower container. One of the two pails might be used to combine the two components. In this case, proper disposal of both pails and the cradle would be required after combining the two components, thus creating a significant negative environmental impact.
Another example, generally known as xe2x80x9cbag-in-bagxe2x80x9d, (as exemplified in U.S. Pat. No. 5,353,927) includes a package for housing and mixing two materials; such as an epoxy resin and a polyamine adduct, together to form an adhesive. Two sheets are joined together to form the outer periphery of the bag. A third sheet is secured between the outer sheets and divides the package into two compartments. When the one compartment is ruptured, the adduct contained therein is released into the other compartment and mixing may take place. After the two materials are completely mixed the adhesive is ready for use. However, with regard to large batch sizes, for example, in an industrial installation, it may be cumbersome to mix the components in a flexible bag. Therefore the use of such packaging systems may be impractical in large-scale use.
More commonly, such compounds are sold to consumers in separate containers that, except for their markings, are physically identical to each other. One example of such packaging includes a pair of metal pails, each contained in a separate box. In such a liquid packaging arrangement, each pail is provided with an appropriate amount of a desired component and then packaged in a similar cardboard box. The use of two separate containers creates the possibility that one of the containers might become misplaced or lost, creating a significant waste of the other of the two components. If dropped, the contents of an inner pail may be spilled.
Use of similar containers may increase of contamination of one component with another in the event that a lid from one component is used to cap a container of the other component. This would increase material waste and if not discovered, might increase the likelihood of non-homogenous mixing of components or spoiled batches. Also, use of multiple pail packaging systems (i.e., use of two or more pails) produces a significant amount of packaging waste in addition to the disposal of the mixing vessel after use and emptying thereof. Therefore, the negative environmental impact of such packaging systems can be significant.
As mentioned, the importance of proper mixing is significant in multi-component products. With respect to epoxies, and the like, where proper mixing is required for the compounds to be properly completely reacted, it is especially important to provide an appropriate mixing vessel adapted to receive the components and permit thorough mixing therein.
It would be desirable to provide a package intended to overcome or minimize all of these problems, as well as to present several other advantages.
One aspect of the present invention provides a method of packaging an epoxy coating including filling a first pouch with a polymeric precursor material. A second pouch is filled with a curing agent. The first and second pouches are sealed. The first and second pouches are inserted into a mixing container and the mixing container is sealed. The first pouch can be filled with a first amount of polymeric precursor material. The second pouch can be filled with a second amount of curing agent with the first and second amounts totaling a first volume. The mixing container can have a second volume, with the first volume being greater than about half the second volume.
Other aspects of the present invention include the first volume being from about 50 percent to about 80 percent of the second volume. The first volume can be from about 60 percent to about 75 percent of the second volume. A third pouch can be filled with a colorant and the third pouch can be inserted into the mixing container along the first and second pouches. The third pouch can be filled with a third amount of colorant, the first, second and third amounts totaling a first volume, with the first volume being greater than about half the second volume. The first volume can be from about 50 percent to about 80 percent of the second volume. The first volume can be from about 60 percent to about 75 percent of the second volume.
Another aspect of the present invention includes an epoxy coating preparation kit including a polymeric precursor material filled pouch, a curing agent filled pouch and a mixing container adapted to receive the pouches and allow preparation of the epoxy coating therein. The pouches can be three-ply pouches. The pouches can include inner and outer layers of polyethylene. The pouches can include a middle layer of biaxially oriented nylon. The pouches can be laminated from at least one barrier film material. Each of the pouches can include a removable cap. The mixing container can be a plastic pail. The plastic pail can be made of high-density polyethylene. The mixing container can be a metal pail. The resin filled pouch can contain a first amount of polymeric precursor material, the curing agent filled pouch can contain a second amount of curing agent, the first and second amounts totaling a first volume, the mixing container having a second volume, the first volume being greater than about half the second volume. The first volume can be from about 50 percent to about 80 percent of the second volume. The first volume can be from about 60 percent to about 75 percent of the second volume.
The foregoing and other features and advantages of the invention will become further apparent from the following detailed description of the presently preferred embodiments, read in conjunction with the accompanying drawings. The detailed description and drawings are merely illustrative of the invention rather than limiting, the scope of the invention being defined by the appended claims and equivalents thereof.